Analog Discovery 2 waveform generator

[catfish]

I'm new to the AD2 and I have a question about the wavegen generator

Can I generate a single pulse output with the AD2 with a variable pulse width? I'm trying to use the square wave out and set it for 1 cycle so I can use the Symmetry slider to be able to select the time (width) for the positive portion of the pulse. I then set the offset to cancel so I'm left with only a positive voltage pulse. The problem is that it appears inverted on an actual scope versus what the Waveforms SW shows graphically for the signal I'm trying to generate.

 

I would like 0 volts out, until I manually trigger a positive pulse (variable width) and then return to 0 volts again. Is this possible?

 

Thanks in advance

[attila]

Hi @catfish

By setting phase to high value you can get the 0V initial output.
Make sure you are connecting the W1 to 1+ and 1- to GND. In case you connect the awg to the scope negative input (1-) you see the signal inverted.

[jpeyron]

Hi @catfish,

Here is a forum thread that give a few different ways to create a single pulse. Hopefully this resolves your question if not let us know.

cheers,

Jon

 

[catfish]

Attila,

Your suggestion works well, thanks.

Shouldn't I be able to perform the same settings in the BASIC section as well? That's where I started and it responds very different than what I expect.

Thanks,

 

Catfish

[catfish]

this is the BASIC waveform I was trying to configure and it generates an inverted signal to what I wanted. 

[catfish]

Can anyone tell me if I should expect the same output from the Discovery 2 for similar settings with Basic and Simple? I believe I have configured them the same but get very different outputs.

 

Thanks

[catfish]

OK, I think I understand now. If the displayed waveform on the screen is high at the leading edge, the output will start and end in the high state. If the phase is shifted so the graphic example of the signal is low, then the outputs will idle low after completion of the signal. By doing this the Basic and Simple outputs can be made to match, just watch what the initial and final signal levels are on screen.